Why it wouldn't matter? Just because I like dueling it doesn't mean I dislike MA. Besides, you can do all kind of things in dueling arena, including having your own dueling rules.
Different arenas, different gameplay, DA, MA, AvA, KoTH, they complement each other. Whilst having preferences, I do not limit myself to single arena, nor did I ever say, to anyone, which they should prefer.
I guess I wouldn't expect my opinion to matter if I'm not involved in the activity. I don't limit myself in the game beyond not participating in things I don't feel like participating in. My time in game is limited, so I spend it where I get the most bang for my buck. If my opinion matters in areas I'm not involved, i guess that's flattering, but not necessary.
The one thing I disagree most with in your post is this-
HO shot is a bad choice in all of them, most of the time. It rather distract from solid ACM.
I'd argue against your last statement. As a matter of fact, I think the guns-cold merge detracts from
some solid ACM. I'm tempted to say the same for the HO, but in reality, I'd say that having the HO as a valid tactic
forces solid ACM. Not from an offensive standpoint, but from a defensive standpoint.
A guns-cold merge is like saying "let's skip part of the fight, and jump ahead to what I/we find to be the most fun". Sure, players improve in those later aspects, but I highly suspect that as a result of skipping the first part of the fight, or at least taking the hazardous aspects out, a player's ability to successfully deal with those aspects is weakened.
If that were truly the case, I'd expect accomplished duelists who don't deviate from their guns-cold merge style, to take FQ hits in the MA, and be frustrated by their opponents choice to take those shots when they're presented with the option. I'd expect complaints of HO'er, HO-dweeb, etc to result. I'd expect it to be mainly complaints by the "more-experienced" pilots directed towards the "less-experienced" pilots.
As further speculative "evidence", I'd say that if we were to remove any other hazardous component of the fight, our maneuvering to defend from those aspects would be reduced. Habits would be formed based on the fact that that component of the fight no longer exists, and if that component were re-introduced, our ability to defend against it would be (at least temporarily) reduced.
As an example, imagine if we could no longer shoot our opponent in the low-six. It's as fair to remove that threat as it is to remove the HO (heck, it's a blind spot! How sporting is it to take a shot like that?). Now, if you could no longer take hits from a player in that position, how much effort would be applied to defending from hits fired from that location? Why bother? And further, what if people realized that it was a "safe zone"? The "front" pilot could actually take advantage of that, and maneuver his plane to put his enemy in that "safe zone" and remove his shot opportunity... Now, a year (or 10) later, re-introduce that threat, and make that shot "legitimate". What will the (at least initial) effect be?
I see those same results spawning from repeated guns-cold merges, where there is no threat of taking damage. And, about the only worse-case scenario I can immediately think of would be if HTC removed the collision aspect/threat from the game, or particularly from one well-populated arena. Eeeks! Imagine the whining!
IMO, if we're going to call our dogfighting at all realistic, we need to retain as many realistic aspects/components as possible. Removing any of them reduces the realism, and IMO, makes them more "fraudulent". Just imagine how it would be if we could continue a fight while our plane was burning, or while pilot wounded, or after our tail was shot off.
There is no DA or MA merge. Only good or bad merge. I can assure you that solid merge works equally well in DA as in MA. Hot or cold.
Yes, some merges are fine for both. Not all. Even if the difference is subtle, the guns-cold merge allows a more aggressive stance in the merge, which wouldn't always be possible in a guns-hot merge. In essence, a guns-hot merge requires a certain amount of "caution" or "defensiveness" that isn't required (or rewarded) in a guns cold merge. And, if your opponent "knows" he won't get damaged in the guns-cold merge, what's to stop him from going purely aggressive, with no care for defending against the obvious fact that his opponents guns are pointed in his general direction, and
could be brought to bear?
In that example, I'd argue that a guns cold merge could lead to less-solid ACM, especially if it was used repeatedly, and created "bad" (IMO) habits.
OK, that's your personal choice and is noted, but I really don't see what that has to do with "HO shot or ACM" question in general?
Just because you don't mind HO (or being good enough to avoid it) doesn't mean it's a good choice. Please find me some air combat literature where HO shots are sold as a good choice (rare exceptions noted).
Boy, I swear I said this earlier, but just in case I forgot...
The HO isn't a good choice. It's a bad choice.
Even if I
did find literature somewhere selling it as such, I'd really have trouble being sold on the idea that it
was/is a good choice.
That doesn't mean it isn't occasionally the
best choice. Or that it isn't always a valid, legitimate choice.
Just because it exposes the pilot to harm doesn't make it invalid, or illegitimate. If we used the "harm's way" argument, could we even justify taking off in AH? Heck, even with no enemies around, landing can be hazardous... Anyone in enemy territory at any altitude lower than all enemies is in harm's way. Exposing your six to the enemy in order to use the more-advanced-than-than-the-HO tactic of the BRD puts you in harm's way...